Oscillating packer roller



M. J. FRANKLIN ETAL 3,160,939

OSCILLATI Dec. 15, 1964 NG PACKER ROLLER April 29, 1963 INVE TO MATTHEW J; FRANKLIN PAUL w. K40

ATTOR'NEYS 1964 M. J. FRANKLIN ETAL 3,160,939

OSCILLATING PACKER ROLLER I Filed April 29, 1963 3 Sheets-Sheet 2 INVENTOE 5 MATfl/EM/ J; FRANKLIN PAUL W. K40

ATTOQHEVS Dec. 1964 M. J. FRANKLIN ETAL 3,160,939

OSCILLATING PACKER RQLLER Filed April 29, 1963 3 Sheets-Sheet 3 INVE'H Tolzs MATfI/EM/ J FRANKLIN PAUL. W KAO ATTOEHEYS United States Patent 3,1603% lLLATlNG PACKER RGLLER Matthew 5. Franklin, hater, and ?aul W. Kan, Bakersfield, (Ialih, assignors to Cen-Vi-i-io Pipe Corporation, Shatter, alif., a corporation of Delaware Filed Apr. 2?, 1963, Ser. No. 276,531

' 9 Claims. (ill. 25-436) The invention relates to concrete pipe spinning machines of a type used to form reinforced concrete pipe of relatively large diameters wherein the concrete is placed into a rotating metal mold and after being deposited and brought to the approximate required thickness the inside surface is then rolled smooth and ultimately troweied for the purpose of malcing the inside diameter as smooth as practical.

Reference is made to Patents Nos. 2,671,260 and 2,722,044 which disclose in considerable detail the various steps heretofore practiced and a typical piece of machinery capable of forming concrete pipes in the manner described. Sundiy additional features have also been incorporated into the process such as for example vibrating the pipe mold to give the concrete greater density and uniformity and also pressure rolling employed for smoothing out the interior surface to improve the inside finish.

In order to meet the usual trade demands for reinforced concrete pipe, certain pipe sizes must be manufactured. These sizes vary over a considerable range from 12" diameter pipe to pipe diameters of six to eight feet. The variation, however, is not in increments of even feet or half foot increments and hence a commercial pipe making operation must be capable of forming for stock as well as for special delivery pipes having a diameter of 27", 51", and other sizes as well as pipes of two foot, two and one-half foot, three foot, three and one-half foot diameters and larger sizes.

Because machinery for the manufacture of pipe of this kind is large and expensive, one machine is usually so constructed that it can be readily adjusted to accommodate pipe molds of a great variety of different diameters without need for making changes in the machinery other than to adjust some supporting parts to accommodate molds of different diameters which may be employed with the same basic machinery. The packer roller which is employed for smoothing oii the inside surface of the concrete before troweling is one of the parts which would be inconvenient and expensive to change in order 7 to accommodate molds of different diameters and hence this is one of the standard parts of the machine employed to operate with molds of all different diameters.

Ordinarily, the packer roller is provided on its outside surface with spiral grooves. A very acceptable type of grooving is one consisting of a double spiral with the grooves having a one inch spacing and a two inch lead. A customary outside diameter for the packer roller is eight inches for pipe machine that makes pipe of 18 to 54" inside diameter. Although the eight inch dimension is not a critical size, it is nevertheless one which as a practical matter operates best on the. variety of different diameters of pipe molds customarily employed.

On those occasions where the inside diameter of the pipe might be 24", the circumference of the inside diameter is an even multiple or" the circumference of the packer roller. When this happens, the grooves in the packer roller tend to generate corresponding spiral ridges on the inside surface of the concrete pipe and these must subsequently be smoothed out by troweling.

On those occasions Where the diameter of the inside surface of the concrete pipe is not an even multiple of 'the packer roller diameter, the spiral ridges are not formed to the same extent and the troweling operation is made considerably quicker and easier.

Even though the diameter of the packer roller migh be made something othcrthan eight inches with the hope of minimizing the number of molds of different size where the diameter will be an even multiple of the diameter of the packer roller, there is no convenient size within operating limits of the packer roller which will avoid the creation of spiral ridges on all of the different sizes of pipe molds. Consequently, where heretofore the same packer roller has been used for molds of all of the diiferent sizes, there have always been molds of some sizes where heavy spiral ridging has resulted and this in turn has necessitated strenuous and prolonged troweling in order to iron out the spiral ridges sufficiently to create a desired smooth troweled surface on the interior of the pipe thereby to minimize the frictional resistance of the pipe surface to the flow of liquids through it.

Another circumstance which has also been objectionable in machines heretofore in operation has been undue rearing of end sections of the packer roller along the line of travel with forming rings at the ends of the mold. Considerable force must be applied to the packer roller to press it into engagement with the rings in order to compact the freshly placed concrete sutficiently. Accordingly, even though the spirally grooved portion of the roller may last for a considerable length of time, the end sections tend to wear out relatively soon and need frequent building up with welding metal deposits if the packer roller is to do an effective job of Working over the interior surface.

Among the objects of the invention is to provide a new and improved packer roller assembly for concrete pipe forming machines capable of producing an improved smooth surface on the inside of concrete pipes, the packer roller being of such character that it operates with an equal degree of eiliciency on all types and sizes of rotating molds irrespective of the specific diameter.

Another object of the invention is to provide a new and improved packer roller assembly for use With rotating concrete pipe molds which operates rapidly and efiiciently on the interior surface of molds of all sizes and which can be counted on in all instances to iron out the surface to a high degree of smoothness thereby to substantially minimize subsequent troweling time.

Another object of the invention is to provide a new and improved packer roller assembly for use with concrete pipe forming machine and molds which will economically produce a smoother, morehydraulically eificient interior surface on the concrete pipe products.

Still another object of the invention is to provide a new andimproved packer roller assembly for rotating concrete pipe making machines which more eifectively works over the concrete in the final stages of forming thereby to materially improve the distribution of sand and aggregate in the concrete wall structure as well as to reduce by an appreciable degree the finishing and the troweling time while at the same time improving the ultimate smoothness of the troweled surface. the structure being such as to economize appreciably use of power in the overall process.

Still another object of the invention is toprovide a new and improved packer roller assemblyv for rotating concrete pipe forming machines so constructed that traction surfaces are provided in the form of replaceable Wearing rings which can be quickly and easily removed when worn by a simple servicing operation in order to replace worn rings with new Wearing rings in a sufiicienb ly short length of time to virtually eliminate need for more than two or three extra rollers and to reduce to 3 a minimum down-time of the machinery while changes are being made.

With these and other objects in view, the invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims and illustrated in the accompanying drawings.

In the drawings:

FIGURE 1 is a fragmentary side perspective View of principal portions of the pipe forming machine showing the position of operation of the packer roller with respect to the machine and the pipe mold during operation.

FIGURE '2 is a fragmentary end elevational view of the packer roller and its mounting taken on the line 2-2 of FIGURE 1'.

FIGURE 3 is a fragmentary end elevational view of the opposite end of the packer roller taken on the line 3-3 of FIGURE 1.

FIGURE 4 is a longitudinal sectional view partially foreshortened taken on the line 44 of FIGURE 1.

FIGURE 5 is a fragmentary view of a portion of the interior of the molded concrete pipe showing operation of the packer roller upon the interior surface.

FIGURE 6 is a fragmentary perspective view of the means for fastening the packer roller to its mounting at one end in closed position.

FIGURE 7 is a view similar to FIGURE 6 showing the clamping means in open position.

FIGURE 8 is a fragmentary longitudinal sectional view of one end of the packer roller showing the means of mounting a wearing ring. 7

FIGURE 9 is an end elevational view of the ring as shown in FIGURE 8.

In an embodiment of the invention chosen for the purpose of illustration there is shown significant portions of a concrete pipe spinning machine constructed so as to support and rotate a cylindrical concrete pipe mold or form 10. The illustration has been confined to' only significant portions of the operating structure in the interest of clarity. Stationary supports 11, 12, 13, and 14 anchor on an appropriate supporting surface (not shown) are employed to mount the operating structure. Four trunnion wheels are employed to carry and rotate the mold 10, wheels 15 and 16 being shown at one end rotatably mounted on the support 11 and one wheel 17 of the two wheels at the opposite end being shown rotatably mounted upon the support 14. By appropriate conventional means (not shown) two of the wheels are driven and by their engagement with the mold rotate the mold at a corresponding speed.

To hold the mold in its proper position during operation stabilizer wheels 18, 19, 20, and 21 are employed. Various means for moving the stabilizer wheels into position and holding them in contact with the mold may be employed as, for example, by making use of a column 22 in the case of the stabilizer wheel 19, secured by means of a footing 23 to the support 12. A fixture 24 is adjustably mounted upon the column and carries a pivot arm 25 at the free end of which the stabilizer wheel 19 is rotatably mounted. When the mold is to be mounted upon the wheels the stabilizer wheels are raised out of the way. After the mold is in operative position upon the trunnion wheels the stabilizer wheels are lowered to locations of alignment over,the upper half of the mold until they firmly engage the mold. Adjusted in this fashion when the mold is rotated in the usual fashion it will be held upon the wheels 15, 16, 17 et cetera by the stabilizer wheels and maintained firmly in place during the depositing of the concrete and the final rolling and troweling operation as well.

The packer roller assembly of which the invention herein disclosed forms part consists of a pivot axle 26 attached by 'means of appropriate brackets 27 and 28 to respective supports 12 and 13. An extension 29 on one end as shown in FIGURE 1 carries an arm 30. Similarly, on the other end an extension 31 carries an arm 32. In each instance the arm is pivotally moved with respect to the pivot axle 26 by an appropriate hydraulic cylinder. At the left end this comprises a cylinder 33 and at the right end the cylinder 34 as viewed in FIGURE 1. In the case of the cylinder 33 attachment is made to the arms 36 by employment of a bracket 35. Cylinder ears 36at the other end are pivotally secured to a piston rod 3'7. The cylinder ears are pivotally mounted upon the support 11 by employmentof a mounting axle 38. The cylinder 34 at the other end is similarly mounted.

As shown in greater detail in FIGURE 4 the arm 30 at its movable end is provided with a hub 48 within which is located a bushing 41 which serves as a bearing. The arm 32 is somewhat'difiierently constructed in that there is provided at the movable end a removable bearing assembly shown respectively in closed and open positions in FIGURES 6 and 7 and in its relative location with respect to the apparatus in FIGURE 4. The removable bearing assembly comprises a relatively fixed clamp section 43 having a fixed location upon the arm 32, to which is hinged a relatively movable clamp section 44. A hinge pin 45 engaging hinge sections 46 and 47 of the clamp section 43 and hinge section 48 of the clamp section'44 pivotally secure the two clamp sections together. For convenience, a handle 49 may be provided by means of which the clamp section 44 can bemoved from the open position of FIGURE 7 to the closed position of FIG- URE 6. In the last identified position a lock pin 5t initially extended to unlatched position as in FIGURE 7 is moved into engagement with a bore 51 of the clamp section 44 when in closed position to secure the parts together. In the last defined position a lock pin arm 52 is passed between a lock pin bracket 53 in order to hold the lock pin in engaged position. When the bushing sections are in closed position as shown in FIGURE 6 they engage upon a bushing 54 which in turn serves as a bearing.

The bushings 41 and 54 just described serve as slidable mountings for what may be described as a packer roller subassembly. The packer roller subassernbly consists in the main of a shaft 66 having one reduced end portion 61 at the left end as Viewed in FIGURE 4 slidably mounted in the bushing 41 and a second reduced end portion 62 at the right hand end slid-ably mounted in the bushing sleeve 54. Although the shaft 60 has been identified by a single reference character, good engineering suggests that it be constructed of two separate pieces, namely, a gate portion 63 and a cantilever portion 64. The purpose of these two portions 63 and 64 is to rotatably support thereon a hollow cylindrical roller 65. This is accomplished by providing two bearings 66 and 67 at the gate end and two similar bearings 68 and 69 at the cantilever end. The bearings in each instance follow accepted conventional practice, being mounted in housings 70 on the respective portions of the shaft and in similar housings 71 on respective interior portions of the roller 65. In the chosen embodiment the exterior surface of the roller 65 is spirally grooved. The spiral grooving is achieved in the present embodiment by providing two spiral grooves in parallel relationship with the grooving having a two inch lead and a one inch pitch. That is to say, adjacent grooves are spaced one inch apart longitudinally whereas corresponding points on the, same continuous groove are spaced two inches apart. The grooving is continuous throughout that portion of the roller which lies within the mold or in any event which lies within that portion of the mold in which concrete is deposited.

0n the gate portion of the roller is mounted a wear ring 76 which fits over a reduced end 77 and is held in position by action of an anchor .ring 78. A series of cap screws 79 and washers Sit serve to hold the anchor ring in position, the cap screws being engaged in threaded bores 81 at the outer rim of the reduced end 77 of the shaft, as shown in FIGURES 8 and 9. In FIGURE 8 there is also clearly shown employment of a seal ring 82 retained in position by a snap ring 83, thereby to secure the bearing 67 in position.

Similarly, on the opposite end of the shaft, namely on the cantilever end portion, there is provided a wear ring 84 on a reduced end 85 held in'position by an anchor ring 86. Similar cap screws 79 and appropriate washers also hold the anchor ring 86 in position.

On the gate end there is provided an end ring 87 which forms the end of the mold and determines the depth of a concrete aggregate mix 88 which fills the mold. The end ring further provides an inner annular traction surface 89 which is engaged by the wear ring 76. The end ring 87 as shown is the bell ring of the mold. On the opposite or spigot end of the mold Till there is provided a comparable end ring EEG which also includes an inner annular traction surface 91 in a position of engagement with the wear ring 84. The depth of the ring 99 determines the depth of the concrete mix throughout the mold. The end rings 87 and 90 following conventional practice are removable by means not shown after the concrete aggregate has been suitably hardened and the mold is opened.

As heretofore constructed the roller structure just described is operated in a fixed rotatable mounting with respect to the arms 30 and 32. In the present invention the roller is adapted to be reciprocated in an axial direction for some distance. In the present example the distance is about one and one-half inches under circumstances Where the spiral grooving has a two inch lead and a one inch pitch, as described. The axial displacement is not precisely critical but is selected as one something different from both the pitch and the lead in order to make certain that permanent grooves are not ironed on the interior surface of the concrete aggregate mix in the mold. In order that the roller can be shifted endwise the shaft 69 con sisting of the two parts 63 and s4 is adapted to shift axially within the bushings 41 and 54. To perform the shifting operation, there is provided a hydraulic cylinder 95 at the cantilever end. The cylinder is mounted upon a plate 96 fastened to a mount 97 which in turn is welded or otherwise secured to the movable end of the arm 3%. The hydraulic cylinder constructed in accordance with known practice includes a cylindrical housing 98 providing a chamber 99 in which a piston itltl is adapted to reciprocate between opposite ends, the piston having fastened thereto a piston rod ltll. The piston red 1451 has a threaded engagement with the reduced end portion 61 of the shaft so that by this expedient the piston rod ltil, piston 160, and the shaft are all fastened together and act as a unit.

Feeding the hydraulic cylinder 95 are hydraulic lines 102 and 103 which connect to a suitable manual control 104, fed in turn from a suitable source of hydraulic pressure which is not shown. A control handle 165 may be manipulated manually in order to feed one end or the other of the chamber 99, thereby to reciprocate the piston 1G0 and piston rod 1M from left to right and right to left throughout the preferred distance of one and onehalf inches. The piston rod 101 passes slidably through a hole me which is cut out from the plate 96.

In operation when a pipe mold is to be placed in the machinery the clamp section at the gate end is separated and by appropriate manipulation of the cylinder 34, the arm 32 is Withdrawn to a removed location. This exposes the gate end of the roller subassembly and hence the cylindrical mold Ill can be slid into place on the wheels 15, 16, and 17, et cetera, as the roller subassembly enters the interior of the mold. Once in position, and again by manipulation of the cylinder 34?, the arm 32 is returned to a position of engagement with the shaft and the clamp sections 43 and 44 are closed to the position shown in FIGURE 6. After this has been done, both of the cylinders 33 and 34 are set in operation suflicieut to raise the packer roller and move the wear rings 76 and 84- out of engagement with the appropriate traction surfaces 89 and 91 respectively. Moist aggregate mix is then placed into the interior of the mold by machinery of well known construction and the mold is then initially spun rapidly in order to effectively distribute the aggregate mix throughout the entire interior of the moldand into position of engagement with the end rings 87 and at the opposite ends. The quantity of aggregatemix can be measured with reasonable accuracy as a result of experience and enough is deposited so as to very slightly overfill the interior of the mold. After the initial spin: ning operation the mix has a rough cylindrical form determined substantially by the height of the end rings.

After this initial spinning the packer roller is brought into operation. This is accomplished again by manipulation of the cylinders 33 and 34 which act to draw the wear rings into engagement with the traction surfaces. At the same time and because the spirally grooved portion of the roller has approximately the same outside diameter as the wear rings, the spirally grooved portion is brought into engagement with the interior surface of the aggregate mix. The mold is then turned relatively slowly, and while this rotation is taking place, the roller is caused to roll about the interior surface of the mix by the frictional engagement of the traction surfaces 89 and 91 with the respective wear rings 76 and 84. By' this operation the interior surface of the mix is worked so that coarse aggregate is pressed and evenly distributed below the innermost surface. 7

At the same time, and by manipulation of the manual control 104, the hydraulic cylinder reciprocates the roller in an axial direction throughout the extent of its throw, namely, about one and one-half inch in'the particular embodiment exemplified. This shifting is somewhat arbitrary but should be sufiiciently rapid to occur several times during each rotation of the mold so that there will be no reproduction of the spiral groove on the mix by reason of the presence of spiral grooving on the roller. The endwise rotation has an added advantage in that, because of the roughened surface of the roller, the roughened surface here having the form of spiral grooves further assists in working the coarse aggregate beneath the surface. The overall result is to produce an interior surface which is smooth to a very appreciable degree, leaving no high spots of any consequence. Accordingly when final trowelling of the inside surface is done, only a few rotations are needed to thoroughly and smoothly trowel the interior surface so that a most effective, smooth, and correspondingly low friction charac teristic is achieved. Inasmuch as the troweling operation is a well known operation, details have been omitted in the interest of clarity. It is of importance, however, to state that where the roughened roller is reciprocated in the manner herein shown and described, smoothing of the interior surface of the mix is secured very largely by action of the roller which is somewhat contrary to prior practice where much of the smoothing had to be done during the troweling operation. Hence, although the mechanics of the troweling remains the same, the time needed for effective and even improved troweling is greatly reduced by the reciprocating motion of the roughened roller during final stages of the molding operation.

FIGURE 5 is included to show on one side of the roller the spirally grooved effect 166 on the interior of the aggregate mix, such as would occur in the absence of reciprocating the roller in an axial direction. On the side 107 there is depicted the elimination of the spirally grooved effects in the aggregate which is accomplished by the reciprocating action of the roller 65. Accordingly, even though there might initially be a'tendency to generate spiral grooves on the interior surface of the mix, as soon as that portion of the interior surface reaches the reciprocating roller, all evidence of spiral grooving will be ironed out and eliminated.

7 Very commonly, because of the great pressure exerted by the cylinders 33 and 34 upon the roller for the purposeof effectively compactingthe concrete, considerable pressure is exerted between the wear rings and the traction surfaces. This tends to wear out the wear rings considerably more rapidly than the wear on the spirally grooved portion of the roller. By making the wear rings a properly different hardness than the traction surfaces, the traction surfaces of the end rings are prevented from undue wear. As promptly as there is too much wear upon the wear rings they canivery readily be removed by merely removing the roller subassembly from the arm, removing the cap screws and washers from both ends of the shaft and then removing first the anchor rings '78 and then the wear rings. Preferably the anchor rings slide freely over the reduced ends but the wear rings are sweated into place by a heating operation so that they are nonrotatably attached to the shaft. The wear rings, however, can be either cut away or removed by heating and replaced by new wear rings after which the anchor rings are replaced and secured in position by the cap screws. The operation thus described is a very simple mechanical operation needing'a minimum of tools and accordingly can be quickly performed without the necessity of closing down the operation any longer than may be needed to remove the roller subassembly and replace it by a newly serviced subassembly.

Although in the chosen embodiment a simple hydraulic cylinder 95 has been described as an appropriate means of shifting the roller subassembly in an endwise direction, it will readily be understood that means of other appropriate kinds resulting however in the cndwise shifting of the roller may be also effectively employed.v While the invention has herein been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention which is not to be limited to the details disclosed herein but is to be accorded the full scope'of the claims so as to embrace any and all equivalent devices.

We claim: t

1. In a molded concrete pipe forming machine stationary means including a frame, a hollow cylindrical pipe mold rotatably mounted on the frame during deposit of a sand and aggregate concrete mix on the interior of said mold, said mold having a rotating motion on said frame during a pipe forming cycle, and a packer roller assembly for working the interior surface of the concrete in the mold, said frame including retaining means on the frame for said roller assembly, said roller assembly comprising a rotatable material working sleeve extending throughout the length of said mold, power means operably associated with said stationary means and said roller assembly acting transversely on said roller assembly adapted to impress said sleeve into pressure engagement with concrete in said mold, and power means operably associated with said frame and said roller assembly acting in an axial direction against said roller assembly adapted to reciprocate said sleeve in an axial direction whereby to reciprocate the area of engagement of said sleeve with said concrete in an axial direction while said sleeveris rolling in pressure engagement with the concrete and to create thereby a relatively smooth surface on the interior of said concrete pipe.

2. In a molded concrete pipe forming machine stationary means including a frame, a hollow cylindrical pipe mold rotatably mounted on the frame during deposit of a sand and aggregate concrete mix on the interior of said mold, said mold having a rotating motion on said frame during a pipe forming cycle, and a packer roller assembly for working said concrete in the mold, said frame including retaining means on the frame for said roller assembly, said roller assembly comprising a shaft rotatably mounted on said retaining means and a material working sleeve rotatably mounted on said shaft and extending throughout the length of said mold, power means operatively associated with said stationary means and said roller assembly acting transversely in said roller assembly adapted to impress said sleeveinto pressure engagement with concrete in said mold, and oscillating motor means operatively associated with said frame and the roller assembly acting in an axial direction between said shaft and said retaining means adapted to reciprocate said sleeve in a an axial direction whereby to reciprocate the area of engagement of said sleeve with said concrete in an axial direction while said sleeve is rolling in pressure engagement with the concrete and to create thereby a relatively smooth surface on the interior of said concrete pipe.

3. In a molded concrete pipe forming machine stationary means including a frame, a hollow cylindrical pipe mold rotatably mounted on the frame during deposit of a sand and aggregate concrete mix on the interior of said mold, and a packer roller assembly for working said concrete in the mold and for smoothing the interior surface thereof, said frame including a pivotal support for said roller assembly and arms on the support having ends adjacent opposite ends of said mold, said roller assembly comprising a shaft having opposite ends rotatably and axiallyslidably mounted on said arms and a material working sleeve having a roughened circumference and being rotatably mounted on said shaft and extending throughoutthe length of said mold, fluid power means having one element thereof connected to one of the arms and another relatively movable element thereof connected to the shaft, said fluid power means being adapted to reciprocate said shaft and said sleeve in an axial direction whereby to reciprocate the area of engagement of said sleeve with said concrete in an axial direction while said sleeve is rolling in pressure engagement with the concrete whereby to create a smooth surface on the interior of said concrete pipe.

4. In a molded concrete pipe forming machine a stationary support, a frame, a rotating hollow cylindrical pipe mold and supporting rollers therefor on the frame, power means adapted to rotate said mold, means adapted to deposit a sand and aggregate concrete mix on the interior of said mold, a packer roller assembly for working said concrete in the mold and for smoothing the interior surface thereof, and a pivotal support on the frame for said roller assembly and including arms on the support having ends adjacent opposite ends of said mold, said roller assembly comprising a shaft having opposite ends rotatably and slidably mounted on said arms, a material working sleeve having a spirally grooved circumference and being rotatably mounted on said shaft and extending throughout the length of said mold, power means acting between said shaft and said stationary support adapted to impress said shaft and said sleeve in a general direction 7 radially outwardly of the mold into pressure engagement with concrete in said mold, and oscillating motor means on one of said arms acting in an axial direction against said shaft and operative to reciprocate said shaft in an axial direction whereby to reciprocate the area of engagement of said sleeve with said concrete in 'an axial direction while said sleeve is rolling in pressure engagement with the concrete and to create thereby a relatively smooth surface on the interior of said concrete pipe.

5. "In a molded concrete pipe forming machine a frame, a hollow cylindrical pipe mold rotatably mounted on the frame during deposit of a sand and aggregate concrete mix on the interior of said mold, a packer roller assembly for Working said concrete in the mold and for smoothing the interior surface thereof, and a pivotal support on the frame for said roller assembly, arms on the support having ends adjacent opposite ends of said mold, said roller assembly including a shaft having opposite ends mounted on said arms, said roller assembly .having, an operative position in engagement with said mold and the mix therein, a hub on a movable end of each arm and a cylindrical hub bushing in each hub, opposite ends of said shaft each having a rotatable and axially shiftable mounting in the respective bushing, and motor means adapted to oscillate said sleeve in an axial direction comprising one relatively axially movable member connected to the shaft and another relatively axially movable member connected to the respective arm whereby in response to application of power to said motor means an axially reciprocating movement is induced in said shaft and the sleeve thereon.

6. In a molded concrete pipe forming machine a frame, supporting rollers in the frame for a supporting and rotating hollow cylindrical pipe mold, during deposit of a sand and aggregate concrete mix on the interior of said mold, a pivotal support on the frame, a packer roller assembly having an operative position in engagement with said mold and the mix therein for working said concrete in the mold and for smoothing the interior surface thereof and arms on the support having ends adjacent opposite ends of said mold, said roller assembly comprising a shaft having opposite ends mounted on said arms, a hub on a movable end of each arm and a cylindrical hub bushing in each hub, opposite ends of said shaft each having a rotatable and axially shiftable mounting in the respective bushing, and means adapted to oscillate said roller assembly in an axial direction comprising a hydraulic cylinder having a casing member and a piston member adapted to move axially with respect to each other, a connection between one of said last members and the shaft and a connection between the other of said last members and the respective arm, said piston member comprising a piston rod and a piston on the rod slidable axially in said cylinder and separating said cylinder into a chamber at each end, and hydraulic lines respectively from said chambers to a source of hydraulic power supply whereby in response to application of power alternately to said chambers on opposite sides of said piston an axially reciprocating movement is induced in said shaft and the sleeve thereon.

7. In a molded concrete pipe forming machine a frame, a hollow cylindrical pipe mold rotatably mounted on the frame during deposit of a sand and aggregate concrete mix on the interior of said mold, annular mold end rings at opposite ends of the mold each having an inner annular edge, a pivotal support on the frame, a packer roller assembly having an operative position in engagement with said mold and the mix therein for working said concrete in the mold and for smoothing the interior surface thereof and arms on the support having ends adjacent opposite ends of said mold, said roller assembly comprising a shaft having opposite ends mounted on said arms, a sleeve rotatably mounted on the shaft, a wear ring on the shaft at each end of the sleeve adapted to engage the respective mold flange and a retaining collar on the shaft for each ring, a hub on a movable end of each arm and a cylindrical hub bushing in each hub, opposite ends of said shaft each having a rotatable and axially shiftable mounting in the respective bushing, and means adapted to oscillate said sleeve in an axial direction comprising a cylinder mount on the arm at one end of the shaft, a hydraulic cylinder having a casing member and a piston member adapted to move axially with respect to each other a connection between one of said last members and the shaft, said piston member comprising a piston rod and a piston on the rod slidable axially in said cylinder and separating 19 said cylinder into a chamber at each end, and hydraulic lines respectively from said chambers to a source of hydraulic power supply whereby in response to application of power alternately to said chambers on opposite sides of said piston, an axially reciprocating movement is induced in said shaft and the sleeve thereon.

8. In a device for molding concrete pipes a cylindrical mold having an annular end ring adjacent each end adapted to gauge the depth of concrete mix deposited in the mold, each said ring having an annular inside traction surface, and a packer roller device adapted to work the concrete mix in said mold between said end rings, said roller device comprising a shaft, pivotal supporting arms for said shaft, a material Working surface on said shaft at a location between said end rings, a replaceable wearing ring at each end of the packer roller having a length greater than the thickness of said traction surface, each said wearing ring being in fixed nonrotating engagement with the shaft, and means for holding each said wearing ring in place comprising an anchor ring on the respective end of the shaft in axial alignment with the wearing ring, circumferentially spaced fastening elements at each end of the shaft adjacent the outside end of each anchor ring, com plementary fastening elements in removable retentive engagement with the anchor rings whereby to hold the anchor rings and wearing rings in position on the shaft.

9. In a device for molding concrete pipes a cylindrical mold having an annular end ring adjacent each end adapted to gauge the depth of concrete mix deposited in the mold, each said end ring having an annular inside traction surface, and a packer roller device adapted to work the concrete mix in said mold between said end rings, said roller device comprising a shaft, a pivotal supporting arm at each end of said shaft, a material working sleeve rotatably mounted on said shaft at a location between said end rings, a replaceable cylindrical wearing ring at each than the thickness of said traction surface, each said wearing ring being in fixed nonrotating engagement with the shaft and having one end in engagement with the respective end of said sleeve, and means for holding each said wearing ring in place comprising a freely sliding cylindrical collar on the respective end of the shaft having one end thereof in engagement with the wearing ring, a transverse annular shoulder on each end of the roller flush with the other end of the respective collar, each said shoulder having circumferentially spaced threaded holes therein and cap screws removably mounted in said holes having heads thereof in retentive engagement with the collars whereby to hold the collars and wearing rings in position on the shaft.

References Cited by the Examiner UNITED STATES PATENTS 1,750,748 3/30 Edmunds 25-30 2,671,260 3/54 Jessen et al. 24-30 2,722,044 11/55 Chanlund et al. 25300 2,724,886 11/55 Kenneson et al. 25-300 2,752,632 7/56 Winstead 18-10 2,945,259 7/ Decker et al. l821 FOREIGN PATENTS 167,877 3/51 Austria. ROBERT F. WHITE, Primary Examiner. 

1. IN A MOLDED CONCRETE PIPE FORMING MACHINE STATIONARY MEANS INCLUDING A FRAME, A HOLLOW CYLINDRICAL PIPE MOLD ROTATABLY MOUNTED ON THE FRAME DURING DEPOSIT OF A SAND AND AGGREGATE CONCRETE MIX ON THE INTERIOR OF SAID MOLD, SAID MOLD HAVING A ROTATING MOTION ON SAID FRAME DURING A PIPE FORMING CYCLE, AND A PACKER ROLLER ASSEMBLY FOR WORKING THE INTERIOR SURFACE OF THE CONCRETE IN THE MOLD, SAID FRAME INCLUDING RETAINING MEANS ON THE FRAME FOR SAID ROLLER ASSEMBLY, SAID ROLLER ASSEMBLY COMPRISING A ROTATABLE MATERIAL WORKING SLEEVE EXTENDING THROUGHOUT THE LENGTH OF SAID MOLD, POWER MEANS OPERABLY ASSOCIATED WITH SAID STATIONARY MEANS AND SAID ROLLER ASSEMBLY ACTING TRANSVERSELY ON SAID ROLLER ASSEMBLY ADAPTED TO IMPRESS SAID SLEEVE INTO PRESSURE ENGAGEMENT WITH CONCRETE IN SAID MOLD, AND POWER MEANS OPERABLY ASSOCIATED WITH SAID FRAME AND SAID ROLLER ASSEMBLY ACTING IN AN AXIAL DIRECTION AGAINST SAID ROLLER ASSEMBLY ADAPTED TO RECIPROCATE SAID SLEEVE IN AN AXIAL DIRECTION WHEREBY TO RECIPROCATE THE AREA OF ENGAGEMENT OF SAID SLEEVE WITH SAID CONCRETE IN AN AXIAL DIRECTION WHILE SAID SLEEVE IS ROLLING IN PRESSURE ENGAGEMENT WITH THE CONCRETE AND TO CREATE THEREBY A RELATIVELY SMOOTH SURFACE ON THE INTERIOR OF SAID CONCRETE PIPE. 